In thinking of ways to relieve the mentioned "stiction" problems, a number of approaches come to mind. For instance, one might consider changing the traditional "circular" path of the slider about the magnetic disc to an elliptical path. This might reduce stiction effects (by imparting a centrifugal force to separate the slider from the disc), but such a solution seems difficult to implement and might present undesirable side effects.
Or, one might curve the slider air-bearing surfaces (rail faces) to reduce plane-to-plane contact with the disc. However, such a curved surface is not easy to visualize and design and is problematic to manufacture in quantity (consistent with yielding a slider that will fly stably just a few micro-inches above a disc). Moreover, the resulting converging/diverging air-flow paths could well make the slider unstable.
Or, one might apply a high frequency vibration to the slider disc just before "start-time" to release the "stiction bond". This has been tried but is not viewed as reliable.
Or, as revealed in the IBM TDB Volume 25, #9 February 1983, one might heat the disc lubricant to reduce its viscosity and thereby hope to reduce stiction. However, this is somewhat impractical, e.g., since it requires special heating means and related power and indicates problematic residual thermal stresses in the slider suspension system.
Thus, the art is still awaiting a practical solution to "stiction" and related problems; a solution which is simpler to implement than the foregoing and which avoids their undesirable side effects. Our invention provides "anti-stiction bosses" as such a solution. For instance, our technique is-very simple to implement and brings no significant adverse side effects. In fact it has been somewhat surprising that such a simple boss means could solve these problems and that such a protruding boss could skid along the disc surface without injuring either itself or the disc. It was also surprising to realize some other advantages using this boss means, such as shorter, quicker "lift off" from the disc, relief of excessive stiction even under "heavy-lube" conditions, and allowing a "low-lube" disc to achieve satisfactory operating life.